1. Field of the Invention
The present invention relates to a medical instrument which is provided with an insertion portion automatically inserted into a subject, an endoscope, and an endoscope device.
2. Description of the Related Art
In recent years, medical instruments such as endoscopes have been widely used in the medical field and industrial field. The endoscope used in the medical field is used for observing organs in a body cavity by inserting an elongated insertion portion into a body cavity as a subject or conducting various treatments using a treatment instrument inserted into an insertion channel of the treatment instrument provided at the endoscope as necessary.
When the insertion portion of a medical endoscope is inserted into a tract in a body cavity such as a colon through an anus, for example, an operator advances the insertion portion in the colon by applying a twisting operation and a feeding operation to a portion located outside the body cavity of the insertion portion and at a bent portion in the colon, the operator advances the insertion portion by bending a bending portion through operation of a bending operating member provided at an operation portion. There is generally known an art to insert the insertion portion to a portion being tested in the colon by the above twisting operation and the feeding operation of the insertion portion and the bending operation of the bending portion.
Here, the above-mentioned insertion operation to the insertion portion of the endoscope, particularly in a colon having a complex and intricate shape, requires skill till the operation can be performed to the depth of the colon smoothly and in a short time.
Therefore, an operator with less experience might take time in operation since the operator loses an insertion direction of the insertion portion, for example, or changes a running state of the colon during performing the insertion operation.
Thus, an endoscope that enables even an operator with less experience to easily insert the insertion portion of the endoscope into a tract in a body cavity and to advance the insertion portion to the portion being tested is in demand.
In view of the above circumstances, Japanese Patent Application Laid-Open Publication No. 2006-034627 discloses a self-propelled endoscope in which a spiral structural body is provided with a spiral shaped portion at a distal end side in an insertion direction of an insertion portion and a thrust is generated at the insertion portion by contact of the spiral structural body with an inner wall of a tract in a body cavity, accompanied by rotary motion, so that the insertion portion is automatically advanced in the tract in the body cavity.
A self-propelled endoscope is also known in which a spiral shaped portion for generating a thrust at the insertion portion by contact with the inner wall of the tract in the body cavity, accompanied by rotary motion, is provided over the entire length of the insertion portion.